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[Tim]

I assembled my pistons on rods and they're tight.
One of them the pin rotates in the piston. The rest rotate on the rod.
These should just free float right?

[92CXyD]

yeah as long as the loose wrist pin has no play and the snap ring are installed properly 

[Tim]

non of them are loose.
I meant the pin is so tight on the rod that it rotates in the piston not on the rod.

Never messed with forged shit, wasn't sure if it was normal and they got looser when it warms up etc.
I called it a night anyway and took em to the machine shop today.

Nothing like planning on assembling your engine and not even getting the crank installed by 3am because of small issues like this.

[crxvtec91]

Any oil or dry?

[ratcityrex]

How tight? Like u needed a press to put them in? Or just snug? I had 3 tight ones and 1 normal one when I got my tt rods put a little oil on then and rotated the pin in with no piston. Just kept putting it in and taking it out. After a few min of this it had a few thousand s clearance and it went together like butter. If I remember correct it should float on the rod too.

[danz]

Either the pin is bent or the pistons or rod small end needs a hone.  Brake hone should do the trick but I would check to see if the wrist pin is bent first with a straight edge (maybe even some glass) and a flash light to look for light peeping through.

[Tim]

snug.  I couldn't push them in by hand, but if I set it on the table I could push them on.
I had a tiny screw driver that fit through the spiroloc, and caught the pin so I could push it all the way in or out on the bench.

The pistons and pins are brand new in box.
I cleaned the pin as they were sticky when I opened them out of the plastic.
used a little 30 wt oil at first, then tried dry as well just to see if it was causing the issue.

I thought about working them on and off a bunch but I said fuck it and decided to let the shop check them out.

Next I'll get them back and they'll be too loose and noisy as hell haha.

[ratcityrex]

Now that I think of it I used a brake hone on mine.